Conventionally, a device that has enabled Extended Coverage (EC)—Global System for Mobile Communications (GSM)—Internet of Things (IoT) operation where Extended Discontinuous Reception (eDRX) is used wakes up to read its nominal paging group according to its negotiated eDRX cycle. As described in 3GPP specifications, if the device does not receive a matching paging message and the EC Page Extension field is included therein, it proceeds as follows:                If the EC Page Extension field indicates that paging extension is enabled for its downlink coverage class, it shall set its eDRX cycle to the lowest eDRX cycle and attempt to read one additional paging message using the first instance of its nominal paging group (calculated using the lowest eDRX cycle) occurring after the last Time Division Multiple Address (TDMA) frame used to transmit the message indicating that paging extension is enabled.        If it finds a matching paging message therein, it shall act on that message.        If paging extension is not enabled or it does not find a matching paging message when attempting to read one additional paging message, it sets its eDRX cycle to the negotiated eDRX cycle, remains in packet idle mode and waits for the next instance of its nominal paging group.        
There are multiple issues accompanying the conventional solution with the lowest eDRX cycle. First, the delay of the pages transmitted using paging extension in Base Transceiver Station (BTS) will be from 2 TDMA frames (˜9.2 ms) when considering devices using coverage class 1 to as large as about eight 51-multiframe (MF) (˜2 sec) when considering devices using coverage class 4.
Second, paging extension will use BTS memory by buffering the pages to be sent using paging extension. The longer the pages are buffered, the more BTS memory will be required. The BTS may discard the buffered pages for paging extension or may discard new received Extended Coverage Common Control Channel (EC-CCCH) messages from Base Station Controller (BSC) if its available buffer space is full.
Third, it is hard for a BTS to predict whether paging extension will be feasible if paging extension maps to a set of TDMA frames that occurs far away from the EC-CCCH TDMA frame under transmission, since the BTS will continue to receive new EC-CCCH messages from BSC before the occurrence of the TDMA frames to be used for paging extension. These new EC-CCCH messages may be prioritized by the BTS and consequently transmitted using a subset of the TDMA frames previously planned to be used for paging extension (in which case a device will fail to read a page message and paging extension fails). In other words, a BTS decision to enable paging extension becomes less likely to result in successfully paging the intended device as the time from the decision to use paging extension until the corresponding planned paging extension increases.
Fourth, EC-CCCH resources may be wasted for the case when there are pages that could be sent in support of paging extension using EC-CCCH blocks that occur before the first instance of a device's nominal paging group (calculated using the lowest eDRX cycle) occurring after the last Time Division Multiple Address (TDMA) frame used to transmit the message indicating that paging extension is enabled.
Fifth, there is no guaranteed gap between the set of Extended Coverage Paging Channel (EC-PCH) blocks (1 EC-PCH block is constructed using the burst information carried by the same timeslot (e.g. timeslot 1) within a pair of consecutive TDMA frames) read to determine that paging extension is enabled and the set of EC-PCH blocks a device determines it needs to read as the first instance of its nominal paging group (calculated using the lowest eDRX cycle) occurring after the last TDMA frame used to transmit the message indicating paging extension is enabled. For example, for Coverage Class 1 (CC1) devices, these two sets of EC-PCH blocks will each consist of 1 EC-PCH block and can occur adjacent to each other (no gap in between), which is not desirable from either a device radio block processing perspective or a BTS page message scheduling perspective.